Weld Quality Verification by Using Laser Triangulation Measurement

Abstract Adaptive welding parameter control and robotic workpiece positioning feedback control impose a strict requirement on the dimensional measurement of the workpieces and fittings. Laser triangulation-based vision systems are commonly used to measure and compensate for the workpiece positioning inaccuracies as well as the inconsistencies of the weld seam. In this study, the laser triangulation system’s accuracy and reliability for welding quality control, workpiece positioning and welding parameter control are analyzed. The combined accuracy of both applied laser sensor and robot are analyzed and compared with the welding requirements. The study shows that the measurement and positioning accuracy of the robot is sufficient on reliable welding torch positioning for reaching and fulfilling the requirements of ISO 5817 level B class weld consistently. The measurement accuracy of the presented system and repeatability of the robot is well within the suitable measurement window for achieving consistent weld quality.